Compounds with (perfluoroalkyl) fluorohydrogenphosphate anions

ABSTRACT

The present invention relates to a process for the preparation of compounds with (perfluoroalkyl)fluorohydrogenphosphate anion, and to compounds containing (perfluoroalkyl)fluorohydrogenphosphate anion and to the use thereof.

The present invention relates to a process for the preparation ofcompounds with (perfluoroalkyl)fluorohydrogenphosphate anion, and tocompounds with (perfluoroalkyl)fluorohydrogenphosphate anion and to theuse thereof.

Onium salts with perfluoroalkylfluorophosphate anions (FAP anions) areemployed as ionic liquids and conductive salts [EP 0929558 B1, WO02/085919 A1, EP 1162204 A1].

An ionic liquid is taken to mean salts which generally consist of anorganic cation and an inorganic anion. They do not contain any neutralmolecules and usually have melting points below 373 K [Wasserscheid P,Keim W, 2000, Angew. Chem. 112: 3926].

Onium salts with an organic cation and a perfluoroalkylfluorophosphateanion (FAP anion) are usually prepared via an exchange reaction of awater-soluble onium salt with, for example, a chloride, bromide,tetra-fluoroborate or triflate anion and perfluoroalkylfluorophosphoricacid (HFAP) or its alkali-metal salts in water [N. V. Ignatyev, U.Welz-Biermann, A. Kucheryna, G. Bissky, H. Willner, 2005, J. FluorineChem. 126: 1150-1159]. HFAP [WO 03/002579] and metal salts thereof canbe prepared from tris(perfluoroalkyl)difluorophosphoranes, which can beobtained by electro-chemical fluorination (Simons process) oftrialkylphosphines [N. V. Ignatyev, P. Sartori, 2000, J. Fluorine Chem.103: 57-61; WO 00/21969]. Organic salts with an FAP anion usually havelimited water solubility and can easily be separated from by-products,which remain in the aqueous solution.

Ionic liquids with FAP anion have high electrochemical and thermalstability and low viscosity. Areas of application of these ionic liquidsare found in organic chemistry (solvents, extraction media, etc.) and inthe material sciences (heat-exchange media, lubricants, conductivesalts, etc.). Ionic liquids having FAP anions are inert materials whichhave much better hydrolytic stability than, for example, ionic liquidshaving PF₆ ⁻ anions. In some cases, however, a medium is desirable whichcan easily be broken down again after the respective process.

The aim of the present invention was thus firstly the provision of anovel process for the preparation of compounds containing(perfluoroalkyl)fluorohydrogenphosphate anions. A further aim of thepresent invention was the provision of novel compounds containing(perfluoroalkyl)fluorohydrogenphosphate anions.

WO 03/087113 discloses a process which facilitates the reduction of(perfluoroalkyl)fluorophosphoranes. Surprisingly, a process has now beenfound which facilitates the addition of a hydride ion onto the substrateduring the reaction of (perfluoroalkyl)fluorophosphorane with a hydrideion donor, giving a (perfluoroalkyl)fluorohydrogenphosphate anion.

The present invention thus relates firstly to a process for thepreparation of a compound of the formula (1)

[Kt]^(x+)[(C_(n)F_(2n+1))_(z)PF_(5-z)H]⁻ _(x)   (1)

in which [Kt]^(x+) is an inorganic or organic cation,

where, in one step, a compound of the formula (2)

(C_(n)F_(2n+1))_(z)PF_(5-z)   (2)

is reacted with a hydride ion donor,

and where, if [Kt]^(x+) is an organic cation, a second step canoptionally be carried out in which the product from the first step isreacted with a compound of the formula (3)

[Kt]^(x+)[X]⁻ _(x)   (3),

in which [Kt]^(x+) stands for an organic cation and [X]⁻ stands for ahydrophilic anion,

in which n=1-8, x=1-4 and z=1-4.

In the literature, bis(trifluoromethyl)difluorohydrogenphosphate([(CF₃)₂PF₃H]⁻) and trifluoromethyltrifluorohydrogenphosphate([CF₃PF₄H]⁻) salts with K⁺ cation and [Me₂NH₂]⁺ cation are described [J.F. Nixon, J. R. Swain, 1968, Chem. Comm.: 997-998; J. F. Nixon, J. R.Swain, 1970, J. Chem. Soc. A: Inorg. Phys. Theor.: 2075-2080; R. G.Cavell, J. F. Nixon, 1964, Proc. Chem. Soc.: 229]. K⁺ [(CF₃)₂PF₃H]⁻ andK⁺ [CF₃PF₄H]⁻ salts are prepared in situ in a reaction ofbis(trifluoromethyl)fluorophosphine ((CF₃)₂PF) ortrifluoromethyldifluorophosphine (CF₃PF₂) with potassium bifluoride in asealed test tube at 60 to 100° C. or in acetonitrile solution at roomtemperature. The corresponding salts with a [Me₂NH₂]⁺ cation areobtained by the reaction of CF₃PF₂ or (CF₃)₂PF with Me₂NH.

These salts have merely been investigated with the aid of ¹⁹F- and¹H-NMR spectroscopic measurements in the reaction mixture. For thesynthesis of [(CF₃)₂PF₃H]⁻ and [CF₃PF₄H]⁻ salts by the method of J. F.Nixon and J. R. Swain, the two starting materialsbis(trifluoromethyl)fluorophosphine (CF₃)₂PF andtrifluoromethyldifluorophosphine CF₃PF₂, which are in the gaseous stateat room temperature and are highly air-sensitive, are necessary. Thesecan be prepared in a complex, multistep synthesis process.

In accordance with the invention, hydride ion donors are compounds whichare capable of releasing one or more hydride ions (H⁻). In the processaccording to the invention, the hydride ion donor is preferably selectedfrom the group comprising metal hydrides, borohydrides, hydridoboratesand hydridoaluminates, but also tertiary and secondary amines.

In a particularly preferred embodiment, metal hydrides are employed;these are very particularly preferably LiAlH₄.

In a further particularly preferred embodiment, use is made of tertiaryor secondary amines of the formula (11):

R¹⁴ ₂N—CH₂R¹⁵   (11),

where

R¹⁴ and R¹⁵ on each occurrence, independently of one another, denotes

-   -   H, where a maximum of one substituent R¹⁴ can be H,    -   straight-chain or branched alkyl having 1-20 C atoms,    -   straight-chain or branched alkenyl having 2-20 C atoms and one        or more double bonds,    -   straight-chain or branched alkynyl having 2-20 C atoms and one        or more triple bonds,    -   saturated, partially or fully unsaturated cycloalkyl having 3-7        C atoms, which may be substituted by alkyl groups having 1-6 C        atoms,

where R¹⁵ may also be Cl or F,

where R¹⁵ may be fully substituted by fluorine and/or one or more R¹⁴and/or R¹⁵ may be partially substituted by halogens or partiallysubstituted by —OR¹*, —NR¹*₂, —CN, —C(O)NR¹*₂ or —SO₂NR¹*₂,

and where one or two non-adjacent carbon atoms which are not in theα-position of the radicals R¹⁴ and/or R₁₅ may be replaced by atomsand/or atom groups selected from the group —O—, —S—, —S(O)—, —SO₂—,—N⁺R¹*₂—, —C(O)NR¹*—, —SO₂NR¹*— or —P(O)R¹*—;

in which R¹* stands for non- or partially fluorinated C₁- to C₆-alkyl,C₃- to C₇-cycloalkyl, unsubstituted or substituted phenyl.

The hydride ion donor used after the process according to the inventioncan be employed either in excess or in equimolar amount, in each casebased on the amount of (perfluoroalkyl)fluorophosphoranes employed. Thehydride ion donor is preferably employed in equimolar amount.

(Perfluoroalkyl)fluorophosphoranes of the formula (2) can be prepared byconventional methods known to the person skilled in the art. Thesecompounds are preferably prepared by electrochemical fluorination ofsuitable starting compounds [V. Y. Semenii et al.,1985, Zh. Obshch.Khim. 55 (12): 2716-2720; N. V. Ignatyev, P. Sartori, 2000, J. FluorineChem. 103: 57-61; WO 00/21969].

In the compound of the formula (2), z preferably stands for 2 or 3; thismeans that formula (2) is preferably selected from the group comprising(C_(n)F_(2n+1))₃PF₂ and (C_(n)F_(2n+1))₂PF₃. z is particularlypreferably =3.

In the compounds of the formula (2), n likewise preferably stands for 2,3 or 4, particularly preferably for 2 or 4. n very particularlypreferably stands for 2, this means that a compound of the formula (2)is very particularly preferably (C₂F₅)_(z)PF_(5-z).

The compounds of the formula (2) are thus very particularly preferably(C₂F₅)₃PF₂.

The cation [Kt]^(x+) in formula (1) of the process according to theinvention can be either an inorganic cation or an organic cation.

If an inorganic cation is present, this is preferably a metal cation.The metal cation is particularly preferably an alkali-metal cation,preferably a lithium, sodium or potassium cation.

If [Kt]^(x+) in formula (1) is an organic cation, this is preferablyselected, exactly like [Kt]^(x+) in formula (3), from the groupcomprising ammonium, phosphonium, uronium, thiouronium, sulfonium,oxonium, guanidinium cations, heterocyclic cations and iminium cations,as defined below:

Ammonium cations are given by the general formula (4)

[NR₄]⁺  (4),

where

R in each case, independently of one another, denotes

-   -   H,    -   straight-chain or branched alkyl having 1-20 C atoms,    -   straight-chain or branched alkenyl having 2-20 C atoms and one        or more double bonds,    -   straight-chain or branched alkynyl having 2-20 C atoms and one        or more triple bonds,    -   saturated, partially or fully unsaturated cycloalkyl having 3-7        C atoms, which may be substituted by alkyl groups having 1-6 C        atoms,

where one R may be fully substituted by fluorine and/or one or more Rmay be partially substituted by halogens, in particular —F and/or Cl, orpartially substituted by —OR¹, —NR¹*₂, —CN, —C(O)NR¹ ₂ or —SO₂NR¹ ₂,

and where one or two non-adjacent carbon atoms which are not in theα-position of the radical R may be replaced by atoms and/or atom groupsselected from the group —O—, —S—, —S(O)—, —SO₂—, —N⁺R¹ ₂—, —C(O)NR¹—,—SO₂NR¹— or —P(O)R¹—.

Phosphonium cations are given by the general formula (5)

[PR² ₄]⁺  (5),

where

R² in each case, independently of one another, denotes

-   -   H where all substituents R² cannot simultaneously be H, NR¹ ₂,    -   straight-chain or branched alkyl having 1-20 C atoms,    -   straight-chain or branched alkenyl having 2-20 C atoms and one        or more double bonds,    -   straight-chain or branched alkynyl having 2-20 C atoms and one        or more triple bonds,    -   saturated, partially or fully unsaturated cycloalkyl having 3-7        C atoms, which may be substituted by alkyl groups having 1-6 C        atoms,

where one R² may be fully substituted by fluorine and/or one or more R²may be partially substituted by halogens, in particular —F and/or —Cl,or partially substituted by —OR¹, —CN, —C(O)NR¹ ₂ or —SO₂NR¹ ₂,

and where one or two non-adjacent carbon atoms which are not in theα-position of the R², may be replaced by atoms and/or atom groupsselected from the group —O—, —S—, —S(O)—, —SO₂—, —N⁺R¹ ₂—, —C(O)NR¹—,—SO₂NR¹—, or —P(O)R¹—.

Cations of the formulae (4) and (5) in which all four or threesubstituents R and R² are fully substituted by halogens, for example thetris(trifluoromethyl)methylammonium cation, thetetra(trifluoromethyl)ammonium cation or thetetra(nonafluorobutyl)ammonium cation, are therefore excluded.

Uronium cations are given by the general formula (6)

[C(NR³R⁴)(OR⁵)(NR⁶R⁷)]⁺  (6)

and suitable thiouronium cations are given by the formula (7),

[C(NR³R⁴)(SR⁵)(NR⁶R⁷)]⁺  (7),

where

R³ to R⁷ each, independently of one another, denote

-   -   H, NR¹*₂,    -   straight-chain or branched alkyl having 1 to 20 C atoms,    -   straight-chain or branched alkenyl having 2-20 C atoms and one        or more double bonds,    -   straight-chain or branched alkynyl having 2-20 C atoms and one        or more triple bonds,    -   saturated, partially or fully unsaturated cycloalkyl having 3-7        C atoms, which may be substituted by alkyl groups having 1-6 C        atoms,

where one or more of the substituents R³ to R⁷ may be partiallysubstituted by halogens, in particular —F, or by —OH, —OR¹, —CN,—C(O)NR¹ ₂ or —SO₂NR¹ ₂,

and where one or two non-adjacent carbon atoms which are not in theα-position of R³ to R⁷ may be replaced by atoms and/or atom groupsselected from the group —O—, —S—, —S(O)—, —SO₂—, —N⁺R¹ ₂—, —C(O)NR¹—,—SO₂NR¹—, or —P(O)R¹—.

Sulfonium cations are given by the general formula (12))

[(R^(o))₃S]⁺  (12),

where

R^(o) stands for

-   -   NR^(′″) ₂,    -   straight-chain or branched alkyl having 1-8 C atoms,    -   saturated, partially or fully unsaturated cycloalkyl having 3-7        C atoms, which may be substituted by alkyl groups having 1-6 C        atoms,

where one or more of the substituents R⁰ may be partially substituted byhalogens, in particular —F, or by —OR^(′″), —CN or —N(R^(′″))₂.

Oxonium cations are given by the general formula (13)

[(R^(o) ⁺ )₃O]⁺  (13),

where

R^(o)* stands for

-   -   straight-chain or branched alkyl having 1-8 C atoms,    -   saturated, partially or fully unsaturated cycloalkyl having 3-7        C atoms, which may be substituted by alkyl groups having 1-6 C        atoms,

where one or more of the substituents R⁰* may be partially substitutedby halogens, in particular —F, or by —OR′″, —CN or —N(R^(′″))₂, in whichR′″ stands, independently of one another, for a straight-chain orbranched C₁-C₈-alkyl.

R^(o) and R^(o)* here preferably stand for a straight-chain alkyl having1-8 C atoms, unsubstituted phenyl, or phenyl which is substituted byC₁-C₆-alkyl, OR^(′″), N(R^(′″))₂, CN or F.

R′″ preferably stands for a straight-chain alkyl having 1-8 C atoms, inparticular methyl or ethyl.

Guanidinium cations are given by the general formula (8)

[C(NR⁸R⁹)(NR¹⁰R¹¹)(NR¹²R¹³)]⁺  (8),

where

R⁸ to R¹³ each, independently of one another, denote

-   -   H, NR¹*₂,    -   straight-chain or branched alkyl having 1 to 20 C atoms,    -   straight-chain or branched alkenyl having 2-20 C atoms and one        or more double bonds,    -   straight-chain or branched alkynyl having 2-20 C atoms and one        or more triple bonds,    -   saturated, partially or fully unsaturated cycloalkyl having 3-7        C atoms, which may be substituted by alkyl groups having 1-6 C        atoms,

where one or more of the substituents R⁸ to R¹³ may be partiallysubstituted by halogens, in particular —F, or by —OR¹, —CN, —C(O)NR¹ ₂or —SO₂NR¹ ₂, and where one or two non-adjacent carbon atoms which arenot in the α-position of R⁸ to R¹³ may be replaced by atoms and/or atomgroups selected from the group —O—, —S—, —S(O)—, —SO₂—, —N⁺R¹ ₂—,—C(O)NR¹—, —SO₂NR¹—, or —P(O)R¹—.

Heterocyclic cations are given by the general formula (9)

[HetN]⁺  (9),

where [HetN]⁺ is a heterocyclic cation selected from the groupcomprising

where the substituents R^(1′) to R^(4′) each, independently of oneanother, denote

-   -   H,    -   straight-chain or branched alkyl having 1-20 C atoms,    -   straight-chain or branched alkenyl having 2-20 C atoms and one        or more double bonds,    -   straight-chain or branched alkynyl having 2-20 C atoms and one        or more triple bonds,    -   saturated, partially or fully unsaturated cycloalkyl having 3-7        C atoms, which may be substituted by alkyl groups having 1-6 C        atoms,    -   saturated, partially or fully unsaturated heteroaryl,        heteroaryl-C₁-C₆-alkyl or aryl-C₁-C₆-alkyl,

where the substituents R^(1′), R^(2′), R^(3′) and/or R^(4′) together mayform a ring system,

where one or more substituents R^(1′) to R^(4′) may be partially orfully substituted by halogens, in particular —F and/or —Cl, or partiallysubstituted by —OR¹, —CN, —C(O)NR¹ ₂ or —SO₂NR¹ ₂, but where R^(1′) andR^(4′) cannot simultaneously be fully substituted by halogens, and whereone or two non-adjacent carbon atoms which are not bonded to theheteroatom of the substituents R^(1′) to R^(4′), may be replaced byatoms and/or atom groups selected from the group —O—, —S—, —S(O)—,—SO₂—, —N⁺R¹ ₂—, —C(O)NR¹—, —SO₂NR¹—, or —P(O)R¹—.

Iminium cations are given by the general formula (10)

[R¹⁴ ₂N═CHR¹⁵]⁺  (10),

where

R¹⁴ and R¹⁵ on each occurrence, independently of one another, denotes

-   -   H, where a maximum of one substituent R¹⁴ can be H,    -   straight-chain or branched alkyl having 1-20 C atoms,    -   straight-chain or branched alkenyl having 2-20 C atoms and one        or more double bonds,    -   straight-chain or branched alkynyl having 2-20 C atoms and one        or more triple bonds,    -   saturated, partially or fully unsaturated cycloalkyl having 3-7        C atoms, which may be substituted by alkyl groups having 1-6 C        atoms,

where R¹⁵ may also stand for Cl or F,

where R¹⁵ may be fully substituted by fluorine and/or one or more R¹⁴and/or R¹⁵ may be partially substituted by halogens or partiallysubstituted by —OR¹*, —NR¹*₂, —CN, —C(O)NR¹*₂ or —SO₂NR¹*₂,

and where one or two non-adjacent carbon atoms which are not in theα-position of the radical R¹⁴ and/or R¹⁵ may be replaced by atoms and/oratom groups selected from the group —O—, —S—, —S(O)—, —SO₂—, —N⁺R¹*₂—,—C(O)NR¹*—, —SO₂NR¹*— or —P(O)R¹*—;

R¹ in all above-mentioned definitions stands for H, non- or partiallyfluorinated C₁- to C₆-alkyl, C₃- to C₇-cycloalkyl, unsubstituted orsubstituted phenyl, and R¹* stands for non- or partially fluorinated C₁-to C₆-alkyl, C₃- to C₇-cycloalkyl, unsubstituted or substituted phenyl.

Fully unsaturated cycloalkyl substituents in the sense of the presentinvention are also taken to mean aromatic substituents.

In accordance with the invention, suitable substituents R and R² to R¹³of the compounds of the formulae (4) to (8), besides H, are preferably:C₁- to C₂₀—, in particular C₁- to C₁₄-alkyl groups, and saturated orunsaturated, i.e. also phenyl, C₃- to C₇-cycloalkyl groups, which may besubstituted by C₁- to C₆-alkyl groups, in particular phenyl.

The substituents R and R² in the compounds of the formula (4) or (5) maybe identical or different. In compounds of the formulae (4), three orfour substituents R are preferably identical. In compounds of theformulae (5), the substituents R² are preferably different.

The substituents R and R² are particularly preferably methyl, ethyl,iso-propyl, propyl, butyl, sec-butyl, pentyl, hexyl, octyl, decyl ortetradecyl.

Up to four substituents of the guanidinium cation[C(NR⁸R⁹)(NR¹⁰R¹¹)(NR¹²R¹³)]⁺ may also be connected in pairs in such away that mono-, bi- or polycyclic molecules form.

Without restricting generality, examples of such guanidinium cationsare:

where the substituents R⁸ to R¹⁰ and R¹³ may have an above-mentioned orparticularly preferred meaning.

The carbocycles or heterocycles of the above-mentioned guanidiniumcations may optionally also be substituted by C₁- to C₆-alkyl, C₁- toC₆-alkenyl, CN, NR¹ ₂, F, Cl, Br, I, C₁-C₆-alkoxy, SCF₃, SO₂CF₃ orSO₂NR¹ ₂, where R¹ has an above-mentioned meaning, substituted orunsubstituted phenyl or unsubstituted or substituted heterocycle.

Up to four substituents of the thiouronium cation[C(NR³R⁴)(SR⁵)(NR⁶R⁷)]⁺ may also be connected in pairs in such a waythat mono-, bi- or polycyclic molecules form.

Without restricting generality, examples of such thiouronium cations areindicated below:

in which Y═S

and where the substituents R³, R⁵ and R⁶ may have an above-mentioned orparticularly preferred meaning.

The carbocycles or heterocycles of the above-mentioned molecules mayoptionally also be substituted by C₁- to C₆-alkyl, C₁- to C₆-alkenyl,CN, NR¹ ₂, F, Cl, Br, I, C₁-C₆-alkoxy, SCF₃, SO₂CF₃ or SO₂NR¹ ₂ orsubstituted or unsubstituted phenyl or unsubstituted or substitutedheterocycle, where R¹ has an above-mentioned meaning.

The substituents R³ to R¹³ are each, independently of one another,preferably a straight-chain or branched alkyl group having 1 to 10 Catoms. The substituents R³ and R⁴, R⁶ and R⁷, R⁸ and R⁹, R¹⁰ and R¹¹ andR¹² and R¹³ in compounds of the formulae (7) and (8) may be identical ordifferent. R³ to R¹³ are particularly preferably each, independently ofone another, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl,sec-butyl, phenyl or cyclohexyl, very particularly preferably methyl,ethyl, n-propyl, isopropyl or n-butyl.

In accordance with the invention, suitable substituents R^(1′) to R^(4′)of compounds of the formula (9), besides H, are preferably: C₁- to C₂₀,in particular C₁- to C₁₂-alkyl groups, and saturated or unsaturated,i.e. also aromatic, C₃- to C₇-cycloalkyl groups, which may besubstituted by C₁- to C₆-alkyl groups, in particular phenyl.

The substituents R^(1′) and R^(4′) are each, independently of oneanother, particularly preferably methyl, ethyl, isopropyl, propyl,butyl, sec-butyl, pentyl, hexyl, octyl, decyl, cyclohexyl, phenyl orbenzyl. They are very particularly preferably methyl, ethyl, n-butyl orhexyl. In pyrrolidine, piperidine, indoline, pyrrolidinium, piperidiniumor indolinium compounds, the two substituents R^(1′) and R^(4′) arepreferably different.

The substituent R^(2′) or R^(3′) is in each case, independently of oneanother, in particular H, methyl, ethyl, isopropyl, propyl, butyl,sec-butyl, tert-butyl, cyclohexyl, phenyl or benzyl. R^(2′) isparticularly preferably H, methyl, ethyl, isopropyl, propyl, butyl orsec-butyl. R^(2′) and R^(3′) are very particularly preferably H.

The C₁-C₁₂-alkyl group is, for example, methyl, ethyl, isopropyl,propyl, butyl, sec-butyl or tert-butyl, furthermore also pentyl, 1-,2-or 3-methylbutyl, 1,1-, 1,2- or 2,2-dimethylpropyl, 1-ethylpropyl,hexyl, heptyl, octyl, nonyl, decyl, undecyl or dodecyl. Optionallydifluoromethyl, trifluoromethyl, pentafluoroethyl, heptafluoropropyl ornonafluorobutyl.

In accordance with the invention suitable substituents R¹⁴ and R¹⁵ ofthe compounds of the formulae (10) and (11), besides H, are preferably:C₁- to C₂₀—, particularly preferably C₁- to C₁₄-alkyl groups and veryparticularly preferably C₁- to C₄-alkyl groups, which may in each casebe unbranched or branched and where one or more radicals R¹⁴ may besubstituted by —NR¹*₂.

The substituents —R¹⁴ and —CH₂—R¹⁵ here may be identical or different.In a preferred embodiment, all three substituents —R¹⁴ and —CH₂—R¹⁵ areidentical. In a further preferred embodiment, two of the substituents—R¹⁴ and —CH₂—R¹⁵ are identical.

The substituents R¹⁴ are particularly preferably H, methyl, ethyl,isopropyl or dimethylaminomethyl.

The substituents R¹⁵ are particularly preferably H or methyl.

The compound of the formula (11) is preferably selected from thecompounds of the formula N(CH₃)₃, N(C₂H₅)₃, HN(C₂H₅)₂,(CH₃)₂N—CH₂—N(CH₃)₂ or CH₃N((CH(CH₃)₂)₂.

A straight-chain or branched alkenyl having 2 to 20 C atoms, where, inaddition, a plurality of double bonds may be present, is, for example,allyl, 2-or 3-butenyl, isobutenyl, sec-butenyl, furthermore 4-pentenyl,iso-pentenyl, hexenyl, heptenyl, octenyl, —C₉H₁₇, —C₁₀H₁₉ to —C₂₀H₃₉;preferably allyl, 2- or 3-butenyl, isobutenyl, sec-butenyl, preferenceis furthermore given to 4-pentenyl, isopentenyl or hexenyl.

A straight-chain or branched alkynyl having 2 to 20 C atoms, where, inaddition, a plurality of triple bonds may be present, is, for example,ethynyl, 1- or 2-propynyl, 2- or 3-butynyl, furthermore 4-pentynyl,3-pentynyl, hexynyl, heptynyl, octynyl, —C₉H₁₅, —C₁₀H₁₇ to —C₂₀H₃₇,preferably ethynyl, 1- or 2-propynyl, 2- or 3-butynyl, 4-pentynyl,3-pentynyl or hexynyl.

Aryl-C₁-C₆-alkyl denotes, for example, benzyl, phenylethyl,phenylpropyl, phenylbutyl, phenylpentyl or phenylhexyl, where both thephenyl ring and also the alkylene chain may be partially or fullysubstituted, as described above, by halogens, in particular —F and/or—Cl, or partially substituted by —OR¹, —NR¹ ₂, —CN, —C(O)NR¹ ₂, —SO₂NR¹₂.

Unsubstituted saturated or partially or fully unsaturated cycloalkylgroups having 3-7 C atoms are therefore cyclopropyl, cyclobutyl,cyclopentyl, cyclohexyl, cycloheptyl, cyclopentenyl, cyclohexenyl,phenyl, cycloheptenyl, each of which may be substituted by C₁- toC₆-alkyl groups, where the cycloalkyl group or the cycloalkyl groupwhich is substituted by C₁- to C₆-alkyl groups may in turn also besubstituted by halogen atoms, such as F, Cl, Br or I, in particular F orCl, or by —OR¹, —CN, —C(O)NR¹ ₂, —SO₂NR¹ ₂.

In the substituents R, R² to R¹³ or R^(1′) to R^(4′), one or twonon-adjacent carbon atoms which are not bonded in the α-position to theheteroatom may also be replaced by atoms and/or atom groups selectedfrom the group —O—, —S—, —S(O)—, —SO₂—, —N⁺R¹ ₂—, —C(O)NR¹—, —SO₂NR¹—,or —P(O)R¹—, where R¹=non-, partially or perfluorinated C₁- to C₆-alkyl,C₃- to C₇-cycloalkyl, unsubstituted or substituted phenyl.

Without restricting generality, examples of substituents R, R² to R¹³and R^(1′) to R^(4′) modified in this way are: —OCH₃, —OCH(CH₃)₂,—CH₂OCH₃, —CH₂—CH₂—O—CH₃, —C₂H₄OCH(CH₃)₂, —C₂H₄SC₂H₅, —C₂H₄SCH(CH₃)₂,—S(O)CH₃, —SO₂CH₃, —SO₂C₆H₅, —SO₂C₃H₇, —SO₂CH(CH₃)₂, —SO₂CH₂CF₃,—CH₂SO₂CH₃, —O—C₄H₈—)—C₄H₉, —CF₃, —C₂F₅, —C₃F₇, —C₄F₉, —C(CF₃)₃,—CF₂SO₂CF₃, —C₂F₄N(C₂F₅)C₂F₅, —CHF₂, —CH₂CF₃, —C₂F₂H₃, —C₃FH₆, —CH₂C₃F₇,—C(CFH₂)₃, —CH₂C₆H₅ or P(O)(C₂H₅)₂.

In R¹, C₃- to C₇-cycloalkyl is, for example, cyclopropyl, cyclobutyl,cyclopentyl, cyclohexyl or cycloheptyl.

In R¹, substituted phenyl means phenyl which is substituted by C₁- toC₆-alkyl, C₁- to C₆-alkenyl, CN, NR¹ ₂, F, Cl, Br, I, C₁-C₆-alkoxy,SCF₃, SO₂CF₃ or SO₂NR*₂, where R* denotes a non-, partially orperfluorinated C₁- to C₆-alkyl or C₃- to C₇-cycloalkyl, as defined forR¹, for example, o-, m- or p-methylphenyl, o-, m- or p-ethylphenyl, o-,m- or p-propylphenyl, o-, m- or p-isopropylphenyl, o-, m- orp-tert-butylphenyl, o-, m- or p-methoxyphenyl, o-, m- or p-ethoxyphenyl,o-, m-, p-(trifluoromethyl)phenyl, o-, m-, p-(trifluoromethoxy)phenyl,o-, m-, p-(trifluoromethylsulfonyl)phenyl, o-, m- or p-fluorophenyl, o-,m- or p-chlorophenyl, o-, m- or p-bromophenyl, o-, m- or p-iodophenyl,further preferably 2,3-, 2,4-, 2,5-, 2,6-, 3,4- or 3,5-dimethylphenyl,2,3-, 2,4-, 2,5-, 2,6-, 3,4- or 3,5-dihydroxyphenyl, 2,3-, 2,4-, 2,5-,2,6-, 3,4-or 3,5-difluorophenyl, 2,3-, 2,4-, 2,5-, 2,6-, 3,4-or3,5-dichloro-phenyl, 2,3-, 2,4-, 2,5-, 2,6-, 3,4- or 3,5-dibromophenyl,2,3-, 2,4-, 2,5-, 2,6-, 3,4- or 3,5-dimethoxyphenyl,5-fluoro-2-methylphenyl, 3,4,5-trimethoxyphenyl or2,4,5-trimethylphenyl.

In R^(1′) to R^(4′), heteroaryl is taken to mean a saturated orunsaturated mono- or bicyclic heterocyclic radical having 5 to 13 ringmembers, where 1, 2 or 3 N and/or 1 or 2 S or O atoms may be present andthe heterocyclic radical may be mono- or polysubstituted by C₁- toC₆-alkyl, C₁- to C₆-alkenyl, CN, NR¹ ₂,F, Cl, Br, I, C₁-C₆-alkoxy, SCF₃,SO₂CF₃ or SO₂NR¹ ₂, where R¹ has a meaning indicated above.

The heterocyclic radical is preferably substituted or unsubstituted 2-or 3-furyl, 2- or 3-thienyl, 1-, 2- or 3-pyrrolyl, 1-, 2-, 4- or5-imidazolyl, 3-, 4- or 5-pyrazolyl, 2-, 4- or 5-oxazolyl, 3-, 4- or5-isoxazolyl, 2-, 4- or 5-thiazolyl, 3-, 4-or 5-isothiazolyl, 2-, 3-or4-pyridyl, 2-, 4-, 5-or 6-pyrimidinyl, furthermore preferably1,2,3-triazol-1-, -4- or -5-yl, 1,2,4-triazol-1-, -4- or -5-yl, 1- or5-tetrazolyl, 1,2,3-oxadiazol-4- or -5-yl 1,2,4-oxadiazol-3- or -5-yl,1,3,4-thiadiazol-2- or -5-yl, 1,2,4-thiadiazol-3- or -5-yl,1,2,3-thiadiazol-4- or -5-yl, 2-, 3-, 4-, 5- or 6-2H-thiopyranyl, 2-, 3-or 4-4H-thiopyranyl, 3- or 4-pyridazinyl, pyrazinyl, 2-, 3-, 4-, 5-,6-or 7-benzofuryl, 2-, 3-, 4-, 5-, 6-or 7-benzothienyl, 1-, 2-, 3-, 4-,5-, 6- or 7-1H-indolyl, 1-, 2-, 4- or 5-benzimidazolyl, 1-, 3-, 4-, 5-,6- or 7-benzopyrazolyl, 2-, 4-, 5-, 6- or 7-benzoxazolyl, 3-, 4-, 5-, 6-or 7-benzisoxazolyl, 2-, 4-, 5-, 6- or 7-benzothiazolyl, 2-, 4-, 5-, 6-or 7-benzisothiazolyl, 4-, 5-, 6- or 7-benz-2,1,3-oxadiazolyl, 1-, 2-,3-, 4-, 5-, 6-, 7- or 8-quinolinyl, 1-, 3-, 4-, 5-, 6-, 7- or8-isoquinolinyl, 1-, 2-, 3-, 4- or 9-carbazolyl, 1-, 2-, 3-, 4-, 5-, 6-,7-, 8- or 9-acridinyl, 3-, 4-, 5-, 6-, 7- or 8-cinnolinyl, 2-, 4-, 5-,6-, 7- or 8-quinazolinyl or 1-, 2- or 3-pyrrolidinyl.

Heteroaryl-C₁-C₆-alkyl is, analogously to aryl-C₁-C₆-alkyl, now taken tomean, for example, pyridinylmethyl, pyridinylethyl, pyridinylpropyl,pyridinylbutyl, pyridinylpentyl, pyridinylhexyl, where, furthermore, theheterocycles described above may be linked to the alkylene chain in thisway.

HetN⁺ is preferably

where the substituents R^(1′) to R^(4′) each, independently of oneanother, have a meaning described above.

The organic cation [Kt]^(x+) is particularly preferably selected fromthe group comprising imidazolium, pyridinium, pyrrolidinium, ammonium,phosphonium or iminium cations, as defined above.

Particularly suitable imidazolium, pyrrolidinium and ammonium cationsare selected from the group tetraalkylammonium,1,1-dialkylpyrrolidinium, 1-alkyl-1-alkoxyalkylpyrrolidnium or1,3-dialkylimidazolium, where the alkyl groups or the alkoxy group inthe alkoxyalkyl group may each, independently of one another, have 1 to10 C atoms. Very particularly preferably, the alkly groups have 1 to 6 Catoms and the alkoxy group has 1 to 3 C atoms. The alkyl groups intetraalkylammonium can therefore be identical or different. Preferably,three alkyl groups are identical and one alkyl group is different or twoalkyl groups are identical and the other two are different. Preferredtetraalkylammonium cations are, for example, trimethyl(ethyl)ammonium,triethyl(methyl)ammonium, tripropyl(methyl)ammonium,tributyl(methyl)ammonium, tripentyl(methyl)ammonium,trihexyl(methyl)ammonium, triheptyl(methyl)ammonium,trioctyl(methyl)ammonium, trinonyl(methyl)ammonium,tridecyl(methyl)ammonium, trihexyl(ethyl)ammonium,ethyl(trioctyl)ammonium, propyl(dimethyl)ethylammonium,butyl(dimethyl)-ethylammonium, methoxyethyl(dimethyl)ethylammonium,methoxyethyl(diethyl)methylammonium,methoxyethyl(dimethyl)propylammonium,ethoxyethyl(dimethyl)ethylammonium. Particularly preferred quaternaryammonium cations are propyl(dimethyl)ethylammonium and/ormethoxyethyl(dimethyl)ethylammonium.

Preferred 1,1-dialkylpyrrolidinium cations are, for example,1,1-dimethylpyrrolidinium, 1-methyl-1-ethylpyrrolidinium,1-methyl-1-propylpyrrolidinium, 1-methyl-1-butylpyrrolidinium,1-methyl-1-pentylpyrrolidinium, 1-methyl-1-hexylpyrrolidinium,1-methyl-1-heptylpyrrolidinium, 1-methyl-1-octylpyrrolidinium,1-methyl-1-nonylpyrrolidinium, 1-methyl-1-decylpyrrolidinium,1,1-diethylpyrrolidinium, 1-ethyl-1-propylpyrrolidinium,1-ethyl-1-butylpyrrolidinium, 1-ethyl-1-pentylpyrrolidinium,1-ethyl-1-hexylpyrrolidinium, 1-ethyl-1-heptylpyrrolidinium,1-ethyl-1-octylpyrrolidinium, 1-ethyl-1-nonylpyrrolidinium,1-ethyl-1-decylpyrrolidinium, 1,1-dipropylpyrrolidinium,1-propyl-1-methylpyrrolidinium, 1-propyl-1-butylpyrrolidinium,1-propyl-1-pentylpyrrolidinium, 1-propyl-1-hexylpyrrolidinium,1-propyl-1-heptylpyrrolidinium, 1-propyl-1-octylpyrrolidinium,1-propyl-1-nonylpyrrolidinium, 1-propyl-1-decylpyrrolidinium,1,1-dibutylpyrrolidinium, 1-butyl-1-methylpyrrolidinium,1-butyl-1-pentylpyrrolidinium, 1-butyl-1-hexylpyrrolidinium,1-butyl-1-heptylpyrrolidinium, 1-butyl-1-octylpyrrolidinium,1-butyl-1-nonylpyrrolidinium, 1-butyl-1-decylpyrrolidinium,1,1-dipentylpyrrolidinium, 1-pentyl-1-hexylpyrrolidinium,1-pentyl-1-heptylpyrrolidinium, 1-pentyl-1-octylpyrrolidinium,1-pentyl-1-nonylpyrrolidinium, 1-pentyl-1-decylpyrrolidinium,1,1-dihexylpyrrolidinium, 1-hexyl-1-heptylpyrrolidinium,1-hexyl-1-octylpyrrolidinium, 1-hexyl-1-nonylpyrrolidinium,1-hexyl-1-decylpyrrolidinium, 1,1-dihexylpyrrolidinium,1-hexyl-1-heptylpyrrolidinium, 1-hexyl-1-octylpyrrolidinium,1-hexyl-1-nonylpyrrolidinium, 1-hexyl-1-decylpyrrolidinium,1,1-diheptylpyrrolidinium, 1-heptyl-1-octylpyrrolidinium,1-heptyl-1-nonylpyrrolidinium, 1-heptyl-1-decylpyrrolidinium,1,1-dioctylpyrrolidinium, 1-octyl-1-nonylpyrrolidinium,1-octyl-1-decylpyrrolidinium, 1-1-dinonylpyrrolidinium,1-nony-1-decylpyrrolidinium or 1,1-didecylpyrrolidinium. Very particularpreference is given to 1-butyl-1-methylpyrrolidinium or1-propyl-1-methylpyrrolidinium.

Preferred 1-alkyl-1-alkoxyalkylpyrrolidinium cations are, for example,1-methoxyethyl-1-methylpyrrolidinium,1-methoxyethyl-1-ethylpyrrolidinium,1-methoxyethyl-1-propylpyrrolidinium,1-methoxyethyl-1-butylpyrrolidinium,1-ethoxyethyl-1-methylpyrrolidinium,1-ethoxymethyl-1-methylpyrrolidinium. Very particular preference isgiven to 1-methoxyethyl-1-methylpyrrolidinium.

Preferred 1,3-dialkylimidazolium cations are, for example,1-ethyl-3-methylimidazolium, 1-methyl-3-propylimidazolium,1-butyl-3-methylimidazolium, 1-methyl-3-pentylimidazolium,1-ethyl-3-propylimidazolium, 1-butyl-3-ethylimidazolium,1-ethyl-3-pentylimidazolium, 1-butyl-3-propylimidazolium,1,3-dimethylimidazolium, 1,3-diethylimidazolium,1,3-dipropypylimidazolium, 1,3-dibutylimidazolium,1,3-dipentylimidazolium, 1,3-dihexylimidazolium,1,3-diheptylimidazolium, 1,3-dioctylimidazolium, 1,3-dinonylimidazolium,1,3-didecylimidazolium, 1-hexyl-3-methylimidazolium,1-heptyl-3-methylimidazolium, 1-methyl-3-octylimidazolium,1-methyl-3-nonylimidazolium, 1-decyl-3-methylimidazolium,1-ethyl-3-hexylimidazolium, 1-ethyl-3-heptylimidazolium,1-ethyl-3-octylimidazolium, 1-ethyl-3-nonylimidazolium or1-decyl-3-ethylimidazolium. Particularly preferred cations are1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium or1-methyl-3-propylimidazolium.

The organic cation [Kt]^(x+) is very particularly preferably a cationselected from the group comprising 1-ethyl-3-methylimidazolium and1-butyl-3-methylimidazolium.

In formula (3) of the process according to the invention, [X]⁻ standsfor a hydrophilic anion. This is preferably an anion selected from thegroup comprising Cl⁻, Br⁻, I⁻, sulfate, sulfonate, acetate and BF₄ ⁻.

A further very particularly preferred embodiment of the presentinvention is a process for the preparation of a compound of the formula(1) as defined above in which [Kt]^(x+) is an iminium cation, where acompound of the formula (2) as defined above is reacted with a tertiaryor secondary amine of the formula (11) as defined above. This embodimenthas the advantage that a compound of the formula (1) containing theorganic iminium cation can be prepared directly in one step without asubsequent metathesis reaction being necessary in a second step. Thefollowing reaction scheme illustrates this reaction by way of example:

The iminium salts formed here are very reactive compounds.

For example, these compounds are intermediates in the Vilsmeier-Haackreaction, Ugi reaction, Houben-Hoesch reaction, Duff reaction andStephen aldehyde synthesis. Iminium salts are, in addition, usefulstarting compounds for the synthesis of β-oxocarboxylic acid esters andβ-diketones [Organikum [Practical Organic Chemistry], WILEY-VCH, 2001,p. 617] or for the synthesis of pyrrolidinium derivatives via a Coperearrangement and intramolecular Mannich reaction [L. E. Overmann, Acc.Chem. Res., 25 (1992), p. 352-359]. Iminium salts react with alcohols(alcoholates), amines, Grignard reagents, alkyl- and aryllithiumcompounds, compounds containing active methyl(CH₂) groups, diazoalkanes(for example CH₂N₂) or 1,3-dienes.

Iminium salts are frequently used in the synthesis of amino compounds,quaternary ammonium salts, aldehydes, ketones, heterocyclic compounds orsteroids [Chemical Encyclopaedia (Russ.) Vol 2, p. 418-419, Moscow,1990].

More recent publications [T. Yamaguchi, et al., Chem and Ind., 1972, p.380; J. of the Am. Chem. Soc., 126 (2004), p. 5968; J. of the Am. Chem.Soc., 128 (2006), p. 5648; J. of the Am. Chem. Soc.,129 (2007), p. 780;J. of the Am. Chem. Soc., 130 (2008), p. 11005; Tetrahedron, 62 (2006),p. 6312; Org. Letters, 6 (2006), p. 4093; Org. Letters, 10 (2008), p.1417; Acc. Chem. Res., 42 (2009), p. 335; Angew. Chem. Int. Ed., 49(2010), p. 3037] show the broad range of applications of iminium salts.The direct synthesis of these salts from tertiary or secondary aminestherefore furthermore enables improvement and simplification of thepreparation of a multiplicity of compounds.

Thus, for example, intermolecular rearrangements can occur starting fromthe iminium salts of the formula (1), where [Kt]^(x+) is an iminiumcation, obtained in the process according to the invention.Alternatively, the iminium salts can also react further spontaneouslywith the nucleophilic reagents, which is depicted by way of example inthe following reaction scheme:

In accordance with the invention, the reaction in the first step of theprocess according to the invention can be carried out at −80 to 50° C.The reaction in the first step is preferably carried out at —20 to 25°C. A temperature of 0° C. is particularly preferred.

The choice of a suitable temperature for the reaction is of particularimportance here in order that, in contrast to the reaction disclosed inWO 03/087113, no reduction of the substrate occurs, but instead theaddition of a hydride ion takes place.

The reaction in the second step of the process according to theinvention is preferably carried out at room temperature.

The reaction in the first step of the process according to the inventionis preferably carried out in an aprotic solvent, such as, for example,dioxane, tetrahydrofuran, diethyl ether, methyl tert-butyl ether,hexane, cyclohexane, benzene, dichloromethane or dichloroethane. Cyclicor linear ethers, such as tetrahydrofuran, diethyl ether or methyltert-butyl ether, are particularly preferably employed. The solvent isvery particularly preferably tetrahydrofuran.

The reaction in the second step of the process according to theinvention is preferably carried out in water or in a mixture of waterand organic solvent.

With the aid of the process according to the invention, various saltshaving (perfluoroalkyl)fluorohydrogenphosphate anions can be prepared ina simple and comfortable manner. The following reaction schemeillustrates the first step of the process according to the inventionwith reference to the reaction of (perfluoroalkyl)fluorophosphoraneswith, for example, LiAlH₄ as hydride ion donor:

The lithium salt obtained in this way, lithium(perfluoroalkyl)fluorohydrogenphosphate(Li[(C_(n)F_(2n+1))_(z)PF_(5-z)H]), is not only of interest for use asconductive salt (such as, for example, in Li ion batteries or insupercapacitors), but can also be used as starting material for thesynthesis of various salts having organic cations (ionic liquids). Thisreaction represents the second step of the process according to theinvention and is illustrated below by way of example:

The present invention therefore likewise relates to the use of acompound of the formula (1) in which [Kt]⁺ is an inorganic cation forthe preparation of a compound of the formula (1) in which [Kt]⁺ is anorganic cation.

For example, ionic liquids can be prepared in this way.

The compounds of the formula (1) in which [Kt]⁺ is an organic cationwhich have been prepared with the aid of the process according to theinvention have a multiplicity of applications:

Thus, owing to their purity, the absent vapour pressure and the highstability as solvent or solvent additive, they are suitable in chemicalreactions. The use as solvent additive takes place in combination withother solvents. Furthermore, the ionic liquids according to theinvention can be employed as phase-transfer catalysts, heat-exchangemedia, as surface-active substances, plasticisers, flameproofing agentsor as conductive salts. In addition, the ionic liquids according to theinvention are suitable as extractants in substance separation processes.

Owing to their electrochemical properties, the ionic liquids accordingto the invention can be employed, in particular, in electrochemicalapplications, such as, for example, as electrolyte in batteries,sensors, accumulators, capacitors or as constituent of a solar cell(solvent and/or electrolyte), preferably a dye solar cell or a sensor.

The ionic liquids prepared with the aid of the process according to theinvention have modified properties, such as, for example, modifiedstability, compared with known ionic liquids.

These hydrophobic ionic liquids can be converted (optionally by heating)into hydrophilic ionic liquids having bis(perfluoroalkyl)phosphinate((C_(n)F_(2n+1))₂P(O)O⁻) or perfluoroalkylphosphonate anion((C_(n)F_(2n+1))P(O)O₂ ⁻²) using water or caustic lye solution:

Owing to these unusual properties of the compounds according to theinvention, different compounds having certain properties can be preparedas required, for example for use in extraction methods. An in situconversion of hydrophobic ionic liquids into hydrophilic ionic liquidsenables the development of a simple isolation method of water-insolubleproducts subsequent to a synthesis in hydrophobic ionic liquids having(perfluoroalkyl)fluorohydrogenphosphate anion.

A further difference of ionic liquids having(perfluoroalkyl)fluorohydrogenphosphate anions from other ionic liquidsis their reduced stability. This can be attributed to the fact that thesymmetry of the (perfluoroalkyl)fluorohydrogenphosphate anions isincreased compared with the FAP anion. On hydrolysis,bis(perfluoroalkyl)phosphinates or perfluoroalkylphosphonates form, asalready depicted with reference to Scheme 3. On continued hydrolysis,phosphates are formed, as depicted below:

Natural products in the form of phosphates (calcium phosphate is usuallyformed in the environment) are thus ultimately obtained.

The present invention furthermore relates to compounds of the formula(1)

[Kt]^(x+)[(C_(n)F_(2n+1))_(z)PF_(5-z)H]⁻ _(x)   (1)

in which [Kt]^(x+) is an inorganic or organic cation,

where n=1-8, x=1-4 and z=1-4,

where the compounds [(CF₃)₂PF₃H]⁻K⁺, [(CF₃)₂PF₃H]⁻[(CH₃)₂NH₂]⁺,[(CF₃)PF₄H]⁻K⁺ and [(CF₃)PF₄H]⁻[(CH₃)₂NH₂]⁺ are excluded.

The cation [Kt]^(x+) of the compounds of the formula (1) according tothe invention can stand for an organic or inorganic cation.

In the case of an inorganic cation, this is preferably a metal cation.Particular preference is given to an alkali-metal cation, preferably alithium, potassium or sodium cation.

Compounds according to the invention having an inorganic cation areparticularly suitable as starting materials for the synthesis ofcompounds according to the invention having organic cations, so-calledionic liquids, as described above.

Particular preference is therefore given to compounds of the formula (1)in which [Kt]^(x+) is an organic cation.

The organic cation is preferably selected from the group comprisingammonium, phosphonium, uronium, thiouronium, sulfonium, oxonium,guanidinium cations, heterocyclic cations and iminium cations, which aredefined as described above.

[Kt]^(x+) of the compound of the formula (1) according to the inventionis particularly preferably an organic cation which is selected from thegroup comprising imidazolium, pyridinium, pyrrolidinium, ammonium,phosphonium, sulfonium and iminium cations, as defined above.

The organic cations [Kt]^(x+) are very particularly preferably a cationselected from the group comprising phenylphosphonium,1-ethyl-3-methyl-imidazolium, 1-butyl-3-methylimidazolium,N-hexylpyridinium and 1-butyl-2,3-dimethylimidazolium.

z in the compounds of the formula (1) according to the inventionpreferably stands for 2 or 3; z is particularly preferably =3.

In addition, n in formula (1) preferably stands for 2, 3 or 4,particularly preferably for 2 or 4. n very particularly preferablystands for 2.

The compounds of the formula (1) are particularly preferably selectedfrom [Kt]^(x+)[(C₂F₅)₃PF₂H]⁻ _(x) or [Kt]^(x+)[(C₂F₅)₂PF₃H]⁻ _(x), inwhich [Kt]^(x+) stands for an organic cation selected from the groupcomprising ammonium, phosphonium, uronium, thiouronium, sulfonium,oxonium, guanidinium cations and heterocyclic cations, as defined above;the compounds are preferably selected from tetraphenylphosphoniumdifluorohydridotris(pentafluoroethyl)-phosphate,1-ethyl-3-methylimidazoliumdifluorohydridotris(pentafluoroethyl)phosphate,1-butyl-3-methylimidazoliumdifluorohydridotris(pentafluoroethyl)phosphate, N-hexylpyrridiniumdifluorohydridotris(pentafluoroethyl)phosphate,N-butyl-N-methylpyrrolidiniumdifluorohydridotris(pentafluoroethyl)phosphate and1-butyl-2,3-dimethylimidazoliumdifluorohydridotris(pentafluoroethyl)phosphate.

As described above, the compounds according to the invention have manydifferent properties which facilitate their use in various areas ofapplication.

The following working examples are intended to explain the inventionwithout limiting it. The invention can be carried out correspondinglythroughout the entire range claimed. Possible variants can also bederived starting from the examples. In particular, the features andconditions of the reactions described in the examples can also beapplied to other reactions which are not shown in detail, but fallwithin the scope of protection of the claims.

EXAMPLES Example 1 Tetraphenylphosphoniumdifluorohydridotris(pentafluoroethyl)phosphate

2.38 g (5.4 mmol) of (C₂F₅)₃PF₂ are slowly added at 0° C. to 5.6 ml of aone molar LiAlH₄/THF solution (5.6 mmol), and the mixture is stirred for20 minutes. The solution is hydrolysed at 0° C. using water, giving acolourless precipitate (aluminium hydroxide), and 1.89 g (5.1 mmol) of[PPh4]Cl in 5 ml of chloroform are added. The precipitate is filteredoff and washed with chloroform. The aqueous phase is separated off, andthe chloroform phase is dried in vacuo, leaving a colourlessprecipitate.

Yield (based on [PPh₄]Cl): 3.18 g (78%)

Melting point: 114-116° C.

TABLE 1.1 ¹⁹F-NMR data of [PPh₄][P(C₂F₅)₃F₂H] in CDCl₃ δ [ppm]Multiplicity J [Hz] Assignment Integral −81.4 m — trans-CF₃ 1.6 −83.1 m— cis-CF₃ 3.3 −113.9 d, d, m ¹J_((PF)) = 737 PF 1 ²J_((FH)) = 58 −120.6d, m ²J_((PF)) = 104 trans-CF₂ 1 −127.3 d, m ²J_((PF)) = 93 cis-CF₂ 2

TABLE 1.2 ³¹P-NMR data of [PPh₄][P(C₂F₅)₃F₂H] in CDCl₃ δ [ppm]Multiplicity J [Hz] Assignment Integral 23.4 s — [PPh₄][(C₂F₅)₃PF₂H] 1−154.9 d, t, quin, t ¹J_((PF)) = 738 [PPh₄][(C₂F₅)₃PF₂H] 0.9²J_((PFtrans)) = 104 ²J_((PFcis)) = 93 ¹J_((PH)) = 678

TABLE 1.3 ¹H-NMR data of [PPh₄][P(C₂F₅)₃F₂H] in CDCl₃ δ [ppm]Multiplicity J [Hz] Assignment Integral 5.6 d, t, t, m ¹J_((PH)) = 678[(C₂F₅)₃PF₂H]⁻ 1 ²J_((HF)) = 64 ³J_((HFtrans)) = 13 7.6-7.9 m —[P(C₆H₅)₄]⁺ 25

TABLE 1.4 Elemental analysis data C H calculated 47.01 2.76 experimental47.15 2.87

TABLE 1.5 Mass-spectrometric data (EI, 20 eV) m/e Rel. intensity [%]Assignment 672 1 [PPh₃(C₂F₅)₃PFH]⁺ 628 0 [PPh₄(C₂F₅)₂PH]⁺ 596 2[PPh₄(C₂F₅)(CF₃)PF₂]⁺ 566 1 [PPh₃(C₂F₅)₂PF₂]⁺ 551 0 [PPh₃(C₂F₅)₂PH]⁺ 5202 [PPh₃(C₂F₅)(CF₃)PF₂]⁺ 490 4 [PPh₂(C₂F₅)₂PF₂]⁺ 444 2[PPh(C₂F₅)(CF₃)PF₂]⁺ 414 13 [PPh(C₂F₅)₂PF₂]⁺ 355 6 [PPh₂(C₂F₅)PF]⁺ 33753 [PPh₄]⁺ 277 7 [PPh(C₂F₅)PF]⁺ 262 100 [PPh₃]⁺ 183 23 [(C₂F₅)PFH]⁺ 1087 [PPh]⁺ 78 9 [Ph]⁺

TABLE 1.6 ESI mass spectrum - negative scan mode Signal Rel. intensity[%] Assignment 307.18 19 [(C₂F₅)₂PF₂]⁻ 417.21 100 [(C₂F₅)₃PF₂H]⁻

Example 2 1-Ethyl-3-methylimidazoliumdifluorohydridotris-(penta-fluoroethyl)phosphate, [EMIM][P(C₂F₅)₃F₂H]

8.1 g (19 mmol) of (C₂F₅)₃PF₂ are slowly added at 0° C. to 20 ml of aone molar LiAlH₄/THF solution (20 mmol), and the mixture is stirred for30 minutes. The solution is hydrolysed using water at 0° C., giving acolourless precipitate (aluminium hydroxide), and 2.8 g (19 mmol) of1-ethyl-3-methylimidazolium chloride, dissolved in 2 ml of water, areadded. After stirring for 30 minutes, the precipitate is filtered off. Asecond phase deposits, which is separated off and extracted twice withwater. It is subsequently dried in vacuo, leaving a colourless liquid.

Yield (based on 1-ethyl-3-methylimidazolium chloride): 3.4 g (33%)

Analytical data of [EMIM][P(C₂F₅)₃F₂H]:

Melting point [° C.] −2.4 Decomposition [° C.] 176 H₂O content [ppm] 43Cl⁻ content [ppm] <5 F⁻ content [ppm] 112

TABLE 2.1 ¹⁹F-NMR data of [EMIM][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment Integral −81.1 m, d ⁴J_((FH)) = 1trans-CF₃ 1 −82.3 quin, d ³J_((PF)) = 9 cis-CF₃ 2 ⁴J_((FH)) = 2 −114.1d, d, m ¹J_((PF)) = 736 PF 0.7 ²J_((FH)) = 64 −119.7 d, m ² _((PF)) =104 trans-CF₂ 0.6 −126.3 d, m ²J_((PF)) = 93 cis-CF₂ 1.2

TABLE 2.2 ³¹P-NMR data of [EMIM][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment −154.4 d, t, quin, t ¹J_((PF)) = 735[C₂F₅)₃PF₂H]⁻ ¹J_((PH)) = 678 ²J_((PFtrans)) = 104 ²J_((PFcis)) = 93

TABLE 2.3 ¹H-NMR data of [EMIM][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment Integral 1.6 t ³J_((HH)) = 7 H7 3 4.0 s —H8 3 4.4 q ³J_((HH)) = 7 H6 2 5.7 d, t, t, m ¹J_((PH)) = 675[(C₂F₅)₃PF₂H]⁻ 1 ²J_((HF)) = 63 ³J_((HFtrans)) = 13 7.7/7.8 t ³J_((HH))= 2 H4/5 2 9.0 s — H2 1

TABLE 2.4 ¹³C{¹H}-NMR data of [EMIM][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment 14.5 s — C7 35.6 s — C8 44.9 s — C6 119.9m — —CF₂CF₃ 122.2 s — C5 122.9 m — —CF₂CF₃ 123.9 s — C4 136.2 s — C2^(a){¹H} ^(b){¹⁹F}

Example 3 1-Butyl-3-methylimidazoliumdifluorohydridotris(pentafluoroethyl)phosphate, [BMIM][P(C₂F₅)₃F₂H]

12.1 g (28.5 mmol) of (C₂F₅)₃PF₂ are slowly added at 0° C. to 30 ml of aone molar LiAlH₄/THF solution (30 mmol), and the mixture is stirred for30 minutes. The solution is hydrolysed using water at 0° C., giving acolourless precipitate (aluminium hydroxide), and 4.9 g (28.5 mmol) of1-butyl-3-methylimidazolium chloride in water are added. After stirringfor 20 minutes, the precipitate is filtered off. A second phasedeposits, which is separated off and extracted twice with water. It issubsequently dried in vacuo, leaving a colourless viscous liquid.

Yield (based on 1-butyl-3-methylimidazolium chloride): 10.2 g (64%)

Analytical data of [BMIM][P(C₂F₅)₃F₂H]:

Glass transition [° C.] −86 Cold crystallisation [° C.] −38 Meltingpoint [° C.] −2.6 Decomposition [° C.] 177 H₂O content [ppm] 40 Cl⁻content [ppm] <5 F⁻ content [ppm] 48

Viscosity and density of [BMIM][P(C₂F₅)₃F₂H]:

T [° C.] ν [mm²/s] ρ [g/cm³] 20 96.48 1.581 30 58.94 1.571 40 38.641.560 50 26.78 1.549 60 19.45 1.538 70 14.65 1.527 80 11.38 1.517

TABLE 3.1 ¹⁹F-NMR data of [BMIM][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment Integral −80.8 m — trans-CF₃ 1 −81.9 m —cis-CF₃ 1.9 −115.0 d, d, m ¹J_((PF)) = 724 PF 0.6 ²J_((FH)) = 65 −119.1d, m ²J_((PF)) = 107 trans-CF₂ 0.6 −125.7 d, m ²J_((PF)) = 92 cis-CF₂1.3

TABLE 3.2 ³¹P-NMR data of [BMIM][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment −154.2 d, t, quin, t ¹J_((PF)) = 737[C₂F₅)₃PF₂H]⁻ ¹J_((PH)) = 676 ²J_((PFtrans)) = 104 ²J_((PFcis)) = 94

TABLE 3.3 ¹H-NMR data of [BMIM][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment Integral 0.9 t ³J_((HH)) = 7 H9 3.1 1.4sext ³J_((HH)) = 8 H8 2.1 1.9 quin ³J_((HH)) = 7 H7 2.2 4.0 s — H10 3.14.4 t ³J_((HH)) = 8 H6 2 5.7 d, t, t, m ¹J_((PH)) = 675 [(C₂F₅)₃PF₂H]⁻0.6 ²J_((HF)) = 63 ³J_((HFtrans)) = 13 7.7 m ³J_((HH)) = 7 H4, H5 2 9.1s — H2 1

TABLE 3.4 ¹³C{¹H}-NMR data of [BMIM][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment 12.7 s — C9 19.0 s — C8 31.8 s — C7 35.7s — C6 49.4 s — C10 118.9 m — —CF₂CF₃ 122.5 s — C4 122.9 m — —CF₂CF₃123.9 s — C5 136.4 s — C2 ^(a){¹H} ^(b){¹⁹F}

Example 4 N-Hexylpyrridiniumdifluorohydridotris(pentafluoroethyl)phosphate, [HPy][P(C₂F₅)₃F₂H]

12.14 g (28.5 mmol) of (C₂F₅)₃PF₂ are slowly added at 0° C. to 30 ml ofa one molar LiAlH₄/THF solution (30 mmol), and the mixture is stirredfor 30 minutes. The solution is hydrolysed using water at 0° C., givinga colourless precipitate (aluminium hydroxide), and 5.67 g (28.5 mmol)of N-hexylpyrridinium chloride, dissolved in 10 ml of water, are added.After stirring for 30 minutes, the precipitate is filtered off. Theemulsion obtained is dried in vacuo. The cloudy, viscous residue isextracted three times with water and again dried in vacuo, leaving acolourless liquid.

Yield (based on N-hexylpyrridinium chloride): 9.98 g (59%)

Analytical data of [HPy][P(C₂F₅)₃F₂H]

Glass transition [° C.] −76 Decomposition [° C.] 166 H₂O content [ppm]27 Cl⁻ content [ppm] 143

TABLE 4.1 ¹⁹F-NMR data of [HPy][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment Integral −79.9 m — trans-CF₃ 1 −81.1 m —cis-CF₃ 2 −112.9 d, d, m ¹J_((PF)) = 737 PF 0.6 ²J_((FH)) = 61 −118.6 d,m ²J_((PF)) = 105 trans-CF₂ 0.5 −125.2 d, m ²J_((PF)) = 92 cis-CF₂ 1.2

TABLE 4.2 ³¹P-NMR data of [HPy][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment −152.7 d, t, quin, t ¹J_((PF)) = 737[C₂F₅)₃PF₂H]⁻ ¹J_((PH)) = 676 ²J_((PFtrans)) = 104 ²J_((PFcis)) = 94

TABLE 4.3 ¹H-NMR data of [HPy][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment Integral 0.9 m H12 3 1.3; 1.9 m H8-H11 94.5 t ³J_((HH)) = 7 H7 2 5.6 d, t, t, m ¹J_((PH)) = 673 [(C₂F₅)₃PF₂H]⁻ 1²J_((HF)) = 63 ³J_((HFtrans)) = 13 8.0 m — H3, H5 2 8.5 t ³J_((HH)) = 8H4 1 8.7 d ³J_((HH)) = 6 H2, H6 2

TABLE 4.4 ¹³C-{¹H}-NMR data of [HPy][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment 13.1 s — C12 22.0 s — C11 25.2 s — C1030.7 s — C9 30.8 s — C8 61.9 s — C7 118.2 m — —CF₂CF₃ 120.9 m — —CF₂CF₃128.4 s — C4 144.4 s — C3, C5 145.7 s — C2, C6 ^(a){¹H} ^(b){¹⁹F}

Example 5 1-Butyl-2,3-dimethylimidazoliumdifluorohydridotris(pentafluoroethyl)phosphate, [BMMIM][P(C₂F₅)₃F₂H]

12.1 g (28.5 mmol) of (C₂F₅)₃PF₂ are slowly added at 0° C. to 30 ml of aone molar LiAlH₄/THF solution (30 mmol), and the mixture is stirred for30 minutes. The solution is hydrolysed using water at 0° C., giving acolourless precipitate (aluminium hydroxide), and 5.4 g (28.5 mmol) of1-butyl-2,3-dimethylimidazolium chloride, dissolved in 2 ml of water,are added. After stirring for 20 minutes, the precipitate is filteredoff. A second phase deposits, which is separated off and extracted twicewith water. It is subsequently dried in vacuo, leaving a colourlessliquid.

Yield (based on 1-butyl-2,3-dimethylimidazolium chloride): 9.1 g (55%)

Analytical data of [BMMIM][P(C₂F₅)₃F₂H]:

Glass transition [° C.] −78 Cold crystallisation [° C.] −24 Meltingpoint [° C.] 9.6 Decomposition [° C.] 179 H₂O content [ppm] 122 Cl⁻content [ppm] 6 F⁻ content [ppm] 198

TABLE 5.1 ¹⁹F-NMR data of [BMMIM][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment Integral −79.9 m — trans-CF₃ 1 −81.1 m —cis-CF₃ 2 −112.9 d, d, m ¹J_((PF)) = 737 PF 0.7 ²J_((FH)) = 65 −118.6 d,m ²J_((PF)) = 105 trans-CF₂ 0.6 −125.1 d, m ²J_((PF)) = 95 cis-CF₂ 1.2

TABLE 5.2 ³¹P-NMR data of [BMMIM][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment −153.7 d, t, quin, t ¹J_((PF)) = 737[C₂F₅)₃PF₂H]⁻ ¹J_((PH)) = 674 ²J_((PFtrans)) = 104 ²J_((PFcis)) = 92

TABLE 5.3 ¹H-NMR data of [BMMIM][P(C₂F₅)₃F₂H] in acetone-d₆ δ [ppm]Multiplicity J [Hz] Assignment Integral 1.0 t ³J_((HH)) = 7 H9 1.5 1.4sext ³J_((HH)) = 7 H8 1 1.9 quin ³J_((HH)) = 7 H7 1 2.8 s — H11 1.5 3.9s — H10 1.6 4.3 t ³J_((HH)) = 7 H6 1.1 5.7 d, t, t, m ¹J_((PH)) = 675[(C₂F₅)₃PF₂H]⁻ — ²J_((HF)) = 63 ³J_((HFtrans)) = 13 7.6 m — H4, H5 1

TABLE 5.4 ¹³C-{¹H}-NMR data of [BMMIM][P(C₂F₅)₃F₂H] in acetone-d₆ δ[ppm] Multiplicity J [Hz] Assignment 8.9 s — C11 12.7 s — C9 19.1 s — C831.2 s — C7 34.6 s — C10 48.0 s — C6 120.8 s C4/5 122.2 s — C4/5 144.4 s— C2

Example 6 Hydrolysis of [EMIm][P(C₂F₅)₃F₂H]

0.72 g of [EMIm][P(C₂F₅)₃PF₂H] are stirred at 110° C. for 8 hours in 10ml of H₂O. Volatile constituents are subsequently removed in vacuo, andthe residue is investigated by NMR spectroscopy.

TABLE 6.1 ³¹P-NMR spectroscopic data of the residue in H₂O δ [ppm]Multiplicity J[Hz] Assignment 5.4 d, t ¹J_((PH)) = 586 (C₂F₅)PH(O)OH²J_((PF)) = 80 2.3 quin ²J_((PF)) = 76 (C₂F₅)₂P(O)OH −3.5 t ²J_((PF)) =78 (C₂F₅)P(O)(OH)₂

Example 7 Synthesis of [Me₂NCH₂NMe₃][P(C₂F₅)₃F₂H]

0.43 g (7.3 mmol) of trimethylamine, NMe₃, are condensed into 5.14 g(12.1 mmol) of tris(pentafluoethyl)difluorophosphorane, (C₂F₅)₃PF₂. Themixture is brought to room temperature, whereupon two phases can beobserved. The mixture is subsequently stirred at room temperature for 24hours. After a few hours, a colourless solid forms. After one day,volatile substances are removed in vacuo, leaving a colourless solid.Yield of the crude product (based on NMe₃) is virtually quantitative(1.99 g).

TABLE 7.1 ³¹P-NMR data of [(CH₃)₂NCH₂N(CH₃)₃][P(C₂F₅)₃F₂H] in CD₃CN δ,ppm Multiplicity J/Hz Assignment −153.7 d, t, quin, t ¹J_((PH)) = 674[P(C₂F₅)₃F₂H]⁻ ¹J_((PF)) = 733 ²J_((PFcis)) = 94 ²J_((PFtrans)) = 104

TABLE 7.2 ¹⁹F-NMR data of [(CH₃)₂NCH₂N(CH₃)₃][P(C₂F₅)₃F₂H] in CD₃CN δ,ppm Multiplicity J/Hz Assignment Integral −80.6 m — trans-CF₃ 3 −81.8 m— cis-CF₃ 6 −113.6 d, d, m, ¹J_((PF)) = 733 PF 2 ²J_((FH)) = 62 −119.1d, m ²J_((PFtrans)) = 104 trans-CF₂ 2 −125.7 d, m ²J_((PFcis)) = 94cis-CF₂ 4

TABLE 7.3 ¹H-NMR spectroscopic data of [(CH₃)₂NCH₂N(CH₃)₃][P(C₂F₅)₃F₂H]in CD₃CN δ, ppm Multiplicity J/Hz Assignment Integral 2.6 s — (CH₃)₂N— 62.8 s — —N(CH₃)₃ 9 4.0 s — —NCH₂N— 2 5.7 d, t, m ¹J_((PH)) = 675[P(C₂F₅)₃PF₂H]⁻ 1 ²J_((FH)) = 63

TABLE 7.4 ¹³C{¹H}-NMR spectroscopic data of[(CH₃)₂NCH₂N(CH₃)₃][P(C₂F₅)₃F₂H] in CD₃CN δ, ppm Multiplicity J/HzAssignment Integral 45.3 s — (CH₃)₂N— 48.4 s — —N(CH₃)₃ 90.5 s — —NCH₂N—

Example 8 Reaction of N(C₂H₅)₃ with (C₂F₅)₃PF₂

0.92 g (9.07 mmol) of triethylamine, NEt₃, are added to 3.77 g (8.85mmol) of tris(pentafluoethyl)difluorophosphorane, (C₂F₅)₃PF₂. Themixture is stirred at room temperature for 24 hours, during which itbecomes an intense brown colour and becomes oily with solid components.Volatile constituents are removed in vacuo. Crude yield: 3.94 g. Thecrude product is dissolved in CH₂Cl₂, and the product,[(C₂H₅)₃NH]—[P(C₂F₅)₃F₂H], is brought to crystallisation at −28° C.

IR(ATR): v(NH) 3203 cm⁻¹

TABLE 8.1 ³¹P-NMR data of [(C₂H₅)₃NH][P(C₂F₅)₃F₂H] in CD₃CN δ, ppmMultiplicity J/Hz Assignment −152.6 d, t, quin, t ¹J_((PH)) = 681[P(C₂F₅)₃F₂H]⁻ ¹J_((PF)) = 723 ²J_((PFtrans)) = 107 ²J_((PFcis)) = 92

TABLE 8.2 ¹⁹F-NMR data of [(C₂H₅)₃NH][P(C₂F₅)₃F₂H] in CD₃CN δ, ppmMultiplicity J/Hz Assignment Integral −81.0 m — trans-CF₃ 3 −82.2“quin”, d 8.5/1 cis-CF₃ 6 −115.3 d, d, m ¹J_((PF)) = 719 [P(C₂F₅)₃F₂H]⁻2 ²J_((HF)) = 62 −119.2 d, m ²J_((PF)) = 107 trans-CF₂ 2 −125.8 d, m²J_((PF)) = 95 cis-CF₂ ([P(C₂F₅)₃F₂H]⁻) 4

TABLE 8.3 ¹H-NMR data of [(C₂H₅)₃NH][P(C₂F₅)₃F₂H] in CD₃CN δ, ppmMultiplicity J/Hz Assignment Integral 1.3 t ³J_((HH)) = 7 —CH₃ 9 3.2quar ³J_((HH)) = 7 —CH₂— 6 5.7 d, quin, t, m ¹J_((PH)) = 645[P(C₂F₅)₃F₂H]⁻ 1 ³J_((FH)) = 13 ³J_((FH)) = 2

TABLE 8.4 ¹³C{¹H}-NMR data of [(C₂H₅)₃NH][P(C₂F₅)₃F₂H] in CD₃CN δ, ppmMultiplicity J/Hz Assignment 8.2 s — —CH₃ 47.0 s — —CH₂—

Example 9 Reaction of HN(C₂H₅)₂ with (C₂F₅)₃PF₂

0.60 g (8.25 mmol) of diethylamine, HNEt₂, are added to 3.44 g (8.08mmol) of tris(pentafluoethyl)difluorophosphorane, (C₂F₅)₃PF₂. Themixture is stirred at room temperature for 24 hours, during which itbecomes an intense brown colour. Volatile constituents are removed invacuo. Crude yield: 3.18 g.

The crude product is dissolved in CH₂Cl₂, and the product,[(C₂H₅)₂NH₂]-[P(C₂F₅)₃F₂H], is brought to crystallisation at −28° C.

TABLE 9.1 ³¹P-NMR data of [(C₂H₅)₂NH₂][P(C₂F₅)₃F₂H] in CD₃CN δ, ppmMultiplicity J/Hz Assignment −153.2 d, t, quin, t ¹J_((PH)) = 679[P(C₂F₅)₃F₂H]⁻ ¹J_((PF)) = 721 ²J_((PFcis)) = 92 ²J_((PFtrans)) = 106

TABLE 9.2 ¹⁹F-NMR data of [(C₂H₅)₂NH₂][P(C₂F₅)₃F₂H] in CD₃CN δ, ppmMultiplicity J/Hz Assignment Integral −81.5 m — trans-CF₃ — −82.8 m —cis-CF₃ — −114.9 d, d, m ¹J_((PF)) = 722 [P(C₂F₅)₃F₂H]⁻ 2 ²J_((HF)) = 65−119.3 d, m ²J_((PFtrans)) = 105 trans-CF₂ 2 −126.0 d, m ²J_((PFcis)) =92 cis-CF₂ 4

TABLE 9.3 ¹H-NMR data of [(C₂H₅)₂NH₂][P(C₂F₅)₃F₂H] in CD₂Cl₂ δ, ppmMultiplicity J/Hz Assignment Integral 1.4 t 7 —CH₃ 1.5 3.1 quar 7 —CH₂—1 5.8 d, t, quin, m ¹J_((PH)) = 681 [P(C₂F₅)₃F₂H]⁻ 0.15 ²J_((HF)) = 63³J_((HFcis)) = 14

TABLE 9.4 ¹³C{¹H}-NMR data of [(C₂H₅)₂NH₂][P(C₂F₅)₃F₂H] in CD₂Cl₂ δ, ppmMultiplicity J/Hz Assignment 10.9 s — —CH₃ 43.6 s — —CH₂—

Example 10 Reaction of Me₂NCH₂NMe₂ with (C₂F₅)₃PF₂

4.5 g (10.6 mmol) of tris(pentafluoethyl)difluorophosphorane,(C₂F₅)₃PF₂, are added at room temperature to 0.88 g (8.6 mmol) ofMe₂NCH₂NMe₂. Two phases can be observed. The mixture is stirred for 24hours, during which a yellow emulsion forms. Excess (C₂F₅)₃PF₂ isremoved in vacuo, and the residue is investigated by NMR spectroscopy.

IR(ATR): v(NH) 3202 cm⁻¹

TABLE 10.1 ³¹P-NMR data of the [P(C₂F₅)₃F₂H] anion in CD₃CN δ, ppmMultiplicity J/Hz Assignment −154.1 d, t, quin, m ¹J_((PH)) = 678[P(C₂F₅)₃F₂H]⁻ ¹J_((PF)) = 730 ²J_((PFcis)) = 93

TABLE 10.2 ¹⁹F-NMR data of the [P(C₂F₅)₃F₂H] anion in CD₃CN δ, ppmMultiplicity J/Hz Assignment −81.1 m — trans-CF₃ −82.4 m — cis-CF₃−113.2 d, d, m ¹J_((PF)) = 724 [P(C₂F₅)₃F₂H]⁻ ²J_((HF)) = 68 −119.3 d, m²J_((PFtrans)) = 118 trans-CF₂ −125.7 d, m ²J_((PFcis)) = 94 cis-CF₂

Example 11 Reaction of i-(C₃H₇)₂NCH₃ with (C₂F₅)₃PF₂

0.82 g (7.12 mmol) of N,N-diisopropylmethylamine are dissolved in 50 mlof diethyl ether, and 3.03 g (7.0 mmol) oftris(pentafluoethyl)difluorophosphorane, (C₂F₅)₃PF₂, are added at roomtemperature. The mixture is stirred for four days and subsequently freedfrom volatile substances in vacuo, leaving a brown solid, which ispurified by recrystallisation from CH₂Cl₂ at −28° C., leaving acolourless solid. Yield: 2.61 g.

TABLE 11.1 ³¹P-NMR data of [((CH₃)₂CH)₂N(H)CH₃][P(C₂F₅)₃F₂H] in CD₃CN δ,ppm Multiplicity J/Hz Assignment −154.4 d, t, quin, t ¹J_((PH)) = 675[P(C₂F₅)₃F₂H]⁻ ¹J_((PF)) = 733 ²J_((PFtrans)) = 104 ²J_((PFcis)) = 94

TABLE 11.2 ¹⁹F-NMR data of [((CH₃)₂CH)₂N(H)CH₃][P(C₂F₅)₃F₂H] in CD₃CN δ,ppm Multiplicity J/Hz Assignment Integral −81.3 m — trans-CF₃ 3 −82.5 m— cis-CF₃ 6 −114.3 d, d, m ¹J_((PF)) = 734 [P(C₂F₅)₃F₂H]⁻ 2 ²J_((HF)) =63 −119.8 d, m ²J_((PFtrans)) = trans-CF₂ 2 105 −126.5 d, m ²J_((PFcis))= 93 cis-CF₂ 4

TABLE 11.3 ¹H-NMR data of [((CH₃)₂CH)₂N(H)CH₃][P(C₂F₅)₃F₂H] in CD₃CN δ,ppm Multiplicity J/Hz Assignment Integral 1.5 d ³J_((HH)) = 7 —CH(CH₃)₂1 2.8 s —NCH₃ 0.2 3.7 sept ³J_((HH)) = 7 —CH(CH₃)₂ 0.15 5.7 d, t, quin,m ¹J_((PH)) = 680 [P(C₂F₅)₃F₂H] 0.15 ²J_((HF)) = 64 ³J_((HFcis)) = 13

TABLE 11.4 ¹³C{¹H}-NMR data of [((CH₃)₂CH)₂N(H)CH₃][P(C₂F₅)₃F₂H] inCD₃CN δ, ppm Multiplicity J/Hz Assignment 19.3 s — CH₃ 32.3 s — NCH₃56.8 s — NCH

Example 12 Reaction of [Me₂NCH₂NMe₃][P(C₂F₅)₃F₂H] with (PhO)₂P(O)H

[(CH₃)₂NCH₂N(CH₃)₃][(C₂F₅)₃PF₂H]+(C₆H₅O)₂P(O)H→(CH₃)₂NCH₂P(O)(OC₆H₅)₂+[HN(CH₃)₃][(C₂F₅)₃PF₂H]

[Me₂NCH₂NMe₃][P(C₂F₅)₃F₂H] is dissolved in CH₂Cl₂, and an excess of(PhO)₂PHO is added. The solution is investigated by NMR spectroscopy.

TABLE 12.1 ³¹P-NMR data of the products in CH₂Cl₂ δ, ppm MultiplicityJ/Hz Assignment 7.3 t ²J_((PCH2)) = 13 Me₂NCH₂P(O)(OPh)₂ −153.8 d, t,quin, t ¹J_((PH)) = 678 [P(C₂F₅)₃F₂H]⁻ ¹J_((PF)) = 731 ²J_((PFtrans)) =104 ²J_((PFcis)) = 93

TABLE 12.2 ¹³C{¹H}-NMR data of the products in CH₂Cl₂ δ, ppmMultiplicity J/Hz Assignment 44.7 s — HN(CH₃)₃ ⁺ 45.1 d ³J_((PC)) = 5(CH₃)₂NCH₂P(O)(OPh)₂ 51.4 d ¹J_((PC)) = 157 (CH₃)₂NCH₂P(O)(OPh)₂

Example 13 Reaction of [Me₂NCH₂NMe₃][P(C₂F₅)₃F₂H] with P(CH₃)₃

[Me₂NCH₂NMe₃][P(C₂F₅)₃F₂H] is dissolved in CH₂Cl₂, and excess P(CH₃)₃ iscondensed on. The solution is investigated by NMR spectroscopy.

TABLE 13.1 ³¹P-NMR data of [(CH₃)₂NCH₂P(CH₃)₃][P(C₂F₅)₃F₂H] in CH₂Cl₂ δ,ppm Multiplicity J/Hz Assignment 24.3 dec, t ²J_((PCH3)) = 13[(CH₃)₂NCH₂P(CH₃)₃]⁺ ²J_((PCH2)) = 4 ¹J_((PC)) = 54 −154.1 d, t, quin, t¹J_((PH)) = 678 [P(C₂F₅)₃F₂H]⁻ ¹J_((PF)) = 728 ²J_((PFtrans)) = 105²J_((PFcis)) = 93

TABLE 13.2 ¹⁹F-NMR data of [(CH₃)₂NCH₂P(CH₃)₃][P(C₂F₅)₃F₂H] in CH₂Cl₂ δ,ppm Multiplicity J/Hz Assignment Integral −80.8 m — trans-CF₃ 3 −82.0 m— cis-CF₃ 6 −113.9 d, d, m ¹J_((PF)) = 730 PF 2 ²J_((FH)) = 63 −119.2 d,m ²J_((PFtrans)) = 105 trans-CF₂ 2 −125.7 d, m ²J_((PFcis)) = 93 cis-CF₂4

TABLE 13.3 ¹H-NMR data of [(CH₃)₂NCH₂P(CH₃)₃][P(C₂F₅)₃F₂H] in CH₂Cl₂ δ,ppm Multiplicity J/Hz Assignment Integral 1.8 d ²J_((PH)) = 14[(CH₃)₂NCH₂P(CH₃)₃]⁺ 9 2.4 s — [(CH₃)₂NCH₂P(CH₃)₃]⁺ 6 3.3 d ²J_((PH)) =5 [(CH₃)₂NCH₂P(CH₃)₃]⁺ 2

TABLE 13.4 ¹³C{¹H}-NMR data of [(CH₃)₂NCH₂P(CH₃)₃][P(C₂F₅)₃F₂H] inCH₂Cl₂ δ, ppm Multiplicity J/Hz Assignment 6.5 d ¹J_((PC)) = 54[(CH₃)₂NCH₂P(CH₃)₃]⁺ 47.6 d ³J_((PC)) = 7 [(CH₃)₂NCH₂P(CH₃)₃]⁺ 51.6 s(br) — N(CH₃)₃ 52.9 d ¹J_((PC)) = 7 [(CH₃)₂NCH₂P(CH₃)₃]⁺

1. Process for the preparation of a compound of the formula (1)[Kt]^(x+)[(C_(n)F_(2n+1))_(z)PF_(5-z)H]⁻ _(x)   (1) in which [Kt]^(x+)is an inorganic or organic cation, where, in one step, a compound of theformula (2)(C_(n)F_(2n+1))_(z)PF_(5-z)   (2) is reacted with a hydride ion donor,and where, if [Kt]^(x+) is an organic cation, a second step canoptionally be carried out in which the product from the first step isreacted with a compound of the formula (3)[Kt]^(x+)[X]⁻ _(x)   (3), in which [Kt]^(x+) stands for an organiccation and [X]⁻ stands for a hydrophilic anion, in which n=1-8, x=1-4and z=1-4.
 2. Process according to claim 1, characterised in that thehydride ion donor is selected from the group comprising metal hydrides,borohydrides, hydridoborates, hydridoaluminates and tertiary andsecondary amines
 3. Process according to claim 2, characterised in thatthe hydride ion donor is LiAlH₄.
 4. Process according to claim 2,characterised in that the hydride ion donor is a tertiary or secondaryamine of the formula (11)R¹⁴ ₂N—CH₂R¹⁵   (11), where R¹⁴ and R¹⁵ on each occurrence,independently of one another, denotes H, where a maximum of onesubstituent R¹⁴ can be H, straight-chain or branched alkyl having 1-20 Catoms, straight-chain or branched alkenyl having 2-20 C atoms and one ormore double bonds, straight-chain or branched alkynyl having 2-20 Catoms and one or more triple bonds, saturated, partially or fullyunsaturated cycloalkyl having 3-7 C atoms, which may be substituted byalkyl groups having 1-6 C atoms, where R¹⁵ may also be Cl or F, whereR¹⁵ may be fully substituted by fluorine and/or one or more R¹⁴ and/orR¹⁵ may be partially substituted by halogens or partially substituted by—OR¹*, —NR¹*₂, —CN, —C(O)NR¹*₂ or —SO₂NR¹*₂, and where one or twonon-adjacent carbon atoms which are not in the α-position of theradicals R¹⁴ and/or R¹⁵ may be replaced by atoms and/or atom groupsselected from the group —O—, —S—, —S(O)—, —SO₂—, —N⁺R¹*₂—, —C(O)NR¹*—,—SO₂NR¹*— or —P(O)R¹*—; in which R¹* stand for non- or partiallyfluorinated C₁- to C₆-alkyl, C₃- to C₇-cycloalkyl, unsubstituted orsubstituted phenyl.
 5. Process according to claim 1, characterised inthat z stands for 2 or
 3. 6. Process according to claim 1, characterisedin that [Kt]^(x+) is a metal cation.
 7. Process according to claim 1,characterised in that [Kt]^(x+) is an organic cation.
 8. Processaccording to claim 7, characterised in that the cation [Kt]^(x+) isselected from the group comprising ammonium, phosphonium, uronium,thiouronium, sulfonium, oxonium, guanidinium cations, heterocycliccations and iminium cations, where ammonium cations are given by thegeneral formula (4)[NR₄]⁺  (4), where R in each case, independently of one another, denotesH, straight-chain or branched alkyl having 1-20 C atoms, straight-chainor branched alkenyl having 2-20 C atoms and one or more double bonds,straight-chain or branched alkynyl having 2-20 C atoms and one or moretriple bonds, saturated, partially or fully unsaturated cycloalkylhaving 3-7 C atoms, which may be substituted by alkyl groups having 1-6C atoms, where one R may be fully substituted by fluorine and/or one ormore R may be partially substituted by halogens or partially substitutedby —OR¹, —NR¹*₂, —CN, —C(O)NR¹ ₂ or —SO₂NR¹ ₂, and where one or twonon-adjacent carbon atoms which are not in the α-position of the radicalR may be replaced by atoms and/or atom groups selected from the group—O—, —S—, —S(O)—, —SO₂—, —N⁺R¹ ₂—, —C(O)NR¹—, —SO₂NR¹— or —P(O)R¹—;where phosphonium cations are given by the general formula (5)[PR² ₄]⁺  (5), where R² in each case, independently of one another,denotes H where all substituents R² cannot simultaneously be H, NR¹ ₂,straight-chain or branched alkyl having 1-20 C atoms, straight-chain orbranched alkenyl having 2-20 C atoms and one or more double bonds,straight-chain or branched alkynyl having 2-20 C atoms and one or moretriple bonds, saturated, partially or fully unsaturated cycloalkylhaving 3-7 C atoms, which may be substituted by alkyl groups having 1-6C atoms, where one R² may be fully substituted by fluorine and/or one ormore R² may be partially substituted by halogens, or partiallysubstituted by —OR¹, —CN, —C(O)NR¹ ₂, —SO₂NR¹ ₂, and where one or twonon-adjacent carbon atoms which are not in the α-position of the R², maybe replaced by atoms and/or atom groups selected from the group —O—,—S—, —S(O)—, —SO₂—, —N⁺R¹ ₂—, —C(O)NR¹—, —SO₂NR¹—, or —P(O)R¹—; whereuronium cations are given by the general formula (6)[C(NR³R⁴)(OR⁵)(NR⁶R⁷)]⁺  (6) and where thiouronium cations are given bythe general formula (7)[C(NR³R⁴)(SR⁵)(NR⁶R⁷)]⁺  (7), where R³ to R⁷ each, independently of oneanother, denote H, NR¹*₂, straight-chain or branched alkyl having 1 to20 C atoms, straight-chain or branched alkenyl having 2-20 C atoms andone or more double bonds, straight-chain or branched alkynyl having 2-20C atoms and one or more triple bonds, saturated, partially or fullyunsaturated cycloalkyl having 3-7 C atoms, which may be substituted byalkyl groups having 1-6 C atoms, where one or more of the substituentsR³ to R⁷ may be partially substituted by halogens, or by —OH, —OR¹, —CN,—C(O)NR¹ ₂, —SO₂NR¹ ₂, and where one or two non-adjacent carbon atomswhich are not in the α-position of R³ to R⁷ may be replaced by atomsand/or atom groups selected from the group —O—, —S—, —S(O)—, —SO₂—,—N⁺R¹ ₂—, —C(O)NR¹—, —SO₂NR¹—, or —P(O)R¹—; where sulfonium cations aregiven by the general formula (12))[(R^(o))₃S]⁺  (12), where R^(o) stands for NR^(′″) ₂, straight-chain orbranched alkyl having 1-8 C atoms, saturated, partially or fullyunsaturated cycloalkyl having 3-7 C atoms, which may be substituted byalkyl groups having 1-6 C atoms, where one or more of the substituentsR⁰ may be partially substituted by halogens, or by —OR^(′″), —CN or—N(R^(′″))₂; where oxonium cations are given by the general formula (13)[(R^(o)*)₃O]⁺  (13), where R^(o)* stands for straight-chain or branchedalkyl having 1-8 C atoms, saturated, partially or fully unsaturatedcycloalkyl having 3-7 C atoms, which may be substituted by alkyl groupshaving 1-6 C atoms, where one or more of the substituents R⁰* may bepartially substituted by halogens, or by —OR′″, —CN or —N(R^(′″))₂;where guanidinium cations are given by the general formula (8)[C(NR⁸R⁹)(NR¹⁰R¹¹)(NR¹²R¹³)]⁺  (8), where R⁸ to R¹³ each, independentlyof one another, denote H, NR¹*₂, straight-chain or branched alkyl having1 to 20 C atoms, straight-chain or branched alkenyl having 2-20 C atomsand one or more double bonds, straight-chain or branched alkynyl having2-20 C atoms and one or more triple bonds, saturated, partially or fullyunsaturated cycloalkyl having 3-7 C atoms, which may be substituted byalkyl groups having 1-6 C atoms, where one or more of the substituentsR⁸ to R¹³ may be partially substituted by halogens or by —OR¹, —CN,—C(O)NR¹ ₂, —SO₂NR¹ ₂, and where one or two non-adjacent carbon atomswhich are not in the α-position of R⁸ to R¹³ may be replaced by atomsand/or atom groups selected from the group —O—, —S—, —S(O)—, —SO₂—,—N⁺R¹ ₂—, —C(O)NR¹—, —SO₂NR¹—, or —P(O)R¹—; where heterocyclic cationsare given by the general formula (9)[HetN]⁺  (9), where [HetN]⁺ is a heterocyclic cation selected from thegroup comprising

where the substituents R^(1′) to R^(4′) each, independently of oneanother, denote H, straight-chain or branched alkyl having 1-20 C atoms,straight-chain or branched alkenyl having 2-20 C atoms and one or moredouble bonds, straight-chain or branched alkynyl having 2-20 C atoms andone or more triple bonds, saturated, partially or fully unsaturatedcycloalkyl having 3-7 C atoms, which may be substituted by alkyl groupshaving 1-6 C atoms, saturated, partially or fully unsaturatedheteroaryl, heteroaryl-C₁-C₆-alkyl or aryl-C₁-C₆-alkyl, where thesubstituents R^(1′), R^(2′), R^(3′) and/or R^(4′) together may form aring system, where one or more substituents R^(1′) to R^(4′) may bepartially or fully substituted by halogens or partially substituted by—OR¹, —CN, —C(O)NR¹ ₂, —SO₂NR¹ ₂, but where R^(1′) and R^(4′) cannotsimultaneously be fully substituted by halogens, and where one or twonon-adjacent carbon atoms which are not bonded to the heteroatom of thesubstituents R^(1′) to R^(4′), may be replaced by atoms and/or atomgroups selected from the group —O—, —S—, —S(O)—, —SO₂—, —N⁺R¹ ₂—,—C(O)NR¹—, —SO₂NR¹—, or —P(O)R¹—; where iminium cations are given by thegeneral formula (10)[R¹⁴ ₂N═CHR¹⁵]⁺  (10), where R¹⁴ and R¹⁵ on each occurrence,independently of one another, denotes H, where a maximum of onesubstituent R¹⁴ can be H, straight-chain or branched alkyl having 1-20 Catoms, straight-chain or branched alkenyl having 2-20 C atoms and one ormore double bonds, straight-chain or branched alkynyl having 2-20 Catoms and one or more triple bonds, saturated, partially or fullyunsaturated cycloalkyl having 3-7 C atoms, which may be substituted byalkyl groups having 1-6 C atoms, where R¹⁵ may also stand for Cl or F,where R¹⁵ may be fully substituted by fluorine and/or one or more R¹⁴and/or R¹⁵ may be partially substituted by halogens or partiallysubstituted by —OR¹*, —NR¹*₂, —CN, —C(O)NR¹*₂ or —SO₂NR¹*₂, and whereone or two non-adjacent carbon atoms which are not in the α-position ofthe radical R¹⁴ and/or R¹⁵ may be replaced by atoms and/or atom groupsselected from the group —O—, —S—, —S(O)—, —SO₂—, —N⁺R¹*₂—, —C(O)NR¹*—,—SO₂NR¹*— or —P(O)R¹*—; in which R¹ stands for H, non- or partiallyfluorinated C₁- to C₆-alkyl, C₃- to C₇-cycloalkyl, unsubstituted orsubstituted phenyl, R¹* stands for non- or partially fluorinated C₁- toC₆-alkyl, C₃- to C₇-cycloalkyl, unsubstituted or substituted phenyl, andR′″ stands for a straight-chain or branched C₁-C₈-alkyl.
 9. Processaccording to claim 1, characterised in that the reaction in the firststep is carried out at −80 to 50° C.
 10. Use of a compound of theformula (1) according to claim 1 in which [Kt]^(x+) is an inorganiccation for the preparation of a compound of the formula (1) according toclaim 1 in which [Kt]^(x+) is an organic cation.
 11. Use of a compoundof the formula (1) according to claim 1 in which [Kt]^(x+) is an organiccation as solvent or solvent additive, as phase-transfer catalyst, asheat-exchange medium, as surface-active substance, as plasticiser, asflameproofing agent, as conductive salt or as extractant in substanceseparation processes.
 12. Use of a compound of the formula (1) accordingto claim 1 in which [Kt]^(x+) is an organic cation in electrochemicalapplications, batteries, sensors, capacitors, solar cells and dye solarcells.
 13. Compound of the formula (1)[Kt]^(x+)[(C_(n)F_(2n+1))_(z)PF_(5-z)H]⁻ _(x)   (1) in which [Kt]^(x+)is an inorganic or organic cation, where n=1-8, x=1-4 and z=1-4, wherethe compounds [(CF₃)₂PF₃H]⁻K⁺, [(CF₃)₂PF₃H]⁻[(CH₃)₂NH₂]⁺, [(CF₃)PF₄H]⁻K⁺and [(CF₃)PF₄H]⁻[(CH₃)₂NH₂]⁺ are excluded.
 14. Compound according toclaim 13, characterised in that [Kt]^(x+) is a metal cation. 15.Compound according to claim 13, characterised in that [Kt]^(x+) is anorganic cation.
 16. Process for the isolation of hydrophobic compounds,characterised in that a compound of the formula (1) according to claim 1in which [Kt]^(x+) stands for an organic cation is converted into acompound containing a [(C_(n)F_(2n+1))₂P(O)O]⁻ or[(C_(n)F_(2n+1))P(O)O₂]⁻² anion by hydrolysis.